X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=folly%2FTraits.h;h=fb797f377bb72a7f860180c8ea511066c15ce0c5;hb=ee207f19892790e091082cc7c7ab8c5df0398061;hp=999a7a257d5238f721d1322ea5bc45b5f030c1f8;hpb=047e9e39c43e16a9c2221406f85fa3d8221c1f35;p=folly.git

diff --git a/folly/Traits.h b/folly/Traits.h
index 999a7a25..fb797f37 100644
--- a/folly/Traits.h
+++ b/folly/Traits.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,10 +18,10 @@
 
 #pragma once
 
-#include <memory>
+#include <functional>
 #include <limits>
+#include <memory>
 #include <type_traits>
-#include <functional>
 
 #include <folly/Portability.h>
 
@@ -36,11 +36,201 @@
 #include <bits/c++config.h>
 #endif
 
-#include <boost/type_traits.hpp>
-#include <boost/mpl/has_xxx.hpp>
+#define FOLLY_CREATE_HAS_MEMBER_TYPE_TRAITS(classname, type_name)              \
+  template <typename TTheClass_>                                               \
+  struct classname##__folly_traits_impl__ {                                    \
+    template <typename UTheClass_>                                             \
+    static constexpr bool test(typename UTheClass_::type_name*) {              \
+      return true;                                                             \
+    }                                                                          \
+    template <typename>                                                        \
+    static constexpr bool test(...) {                                          \
+      return false;                                                            \
+    }                                                                          \
+  };                                                                           \
+  template <typename TTheClass_>                                               \
+  using classname = typename std::conditional<                                 \
+      classname##__folly_traits_impl__<TTheClass_>::template test<TTheClass_>( \
+          nullptr),                                                            \
+      std::true_type,                                                          \
+      std::false_type>::type;
+
+#define FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(classname, func_name, cv_qual) \
+  template <typename TTheClass_, typename RTheReturn_, typename... TTheArgs_> \
+  struct classname##__folly_traits_impl__<                                    \
+      TTheClass_,                                                             \
+      RTheReturn_(TTheArgs_...) cv_qual> {                                    \
+    template <                                                                \
+        typename UTheClass_,                                                  \
+        RTheReturn_ (UTheClass_::*)(TTheArgs_...) cv_qual>                    \
+    struct sfinae {};                                                         \
+    template <typename UTheClass_>                                            \
+    static std::true_type test(sfinae<UTheClass_, &UTheClass_::func_name>*);  \
+    template <typename>                                                       \
+    static std::false_type test(...);                                         \
+  }
+
+/*
+ * The FOLLY_CREATE_HAS_MEMBER_FN_TRAITS is used to create traits
+ * classes that check for the existence of a member function with
+ * a given name and signature. It currently does not support
+ * checking for inherited members.
+ *
+ * Such classes receive two template parameters: the class to be checked
+ * and the signature of the member function. A static boolean field
+ * named `value` (which is also constexpr) tells whether such member
+ * function exists.
+ *
+ * Each traits class created is bound only to the member name, not to
+ * its signature nor to the type of the class containing it.
+ *
+ * Say you need to know if a given class has a member function named
+ * `test` with the following signature:
+ *
+ *    int test() const;
+ *
+ * You'd need this macro to create a traits class to check for a member
+ * named `test`, and then use this traits class to check for the signature:
+ *
+ * namespace {
+ *
+ * FOLLY_CREATE_HAS_MEMBER_FN_TRAITS(has_test_traits, test);
+ *
+ * } // unnamed-namespace
+ *
+ * void some_func() {
+ *   cout << "Does class Foo have a member int test() const? "
+ *     << boolalpha << has_test_traits<Foo, int() const>::value;
+ * }
+ *
+ * You can use the same traits class to test for a completely different
+ * signature, on a completely different class, as long as the member name
+ * is the same:
+ *
+ * void some_func() {
+ *   cout << "Does class Foo have a member int test()? "
+ *     << boolalpha << has_test_traits<Foo, int()>::value;
+ *   cout << "Does class Foo have a member int test() const? "
+ *     << boolalpha << has_test_traits<Foo, int() const>::value;
+ *   cout << "Does class Bar have a member double test(const string&, long)? "
+ *     << boolalpha << has_test_traits<Bar, double(const string&, long)>::value;
+ * }
+ *
+ * @author: Marcelo Juchem <marcelo@fb.com>
+ */
+#define FOLLY_CREATE_HAS_MEMBER_FN_TRAITS(classname, func_name)               \
+  template <typename, typename>                                               \
+  struct classname##__folly_traits_impl__;                                    \
+  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(classname, func_name, );             \
+  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(classname, func_name, const);        \
+  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(                                     \
+      classname, func_name, /* nolint */ volatile);                           \
+  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(                                     \
+      classname, func_name, /* nolint */ volatile const);                     \
+  template <typename TTheClass_, typename TTheSignature_>                     \
+  using classname =                                                           \
+      decltype(classname##__folly_traits_impl__<TTheClass_, TTheSignature_>:: \
+                   template test<TTheClass_>(nullptr))
 
 namespace folly {
 
+/***
+ *  _t
+ *
+ *  Instead of:
+ *
+ *    using decayed = typename std::decay<T>::type;
+ *
+ *  With the C++14 standard trait aliases, we could use:
+ *
+ *    using decayed = std::decay_t<T>;
+ *
+ *  Without them, we could use:
+ *
+ *    using decayed = _t<std::decay<T>>;
+ *
+ *  Also useful for any other library with template types having dependent
+ *  member types named `type`, like the standard trait types.
+ */
+template <typename T>
+using _t = typename T::type;
+
+/**
+ *  type_t
+ *
+ *  A type alias for the first template type argument. `type_t` is useful for
+ *  controlling class-template and function-template partial specialization.
+ *
+ *  Example:
+ *
+ *    template <typename Value>
+ *    class Container {
+ *     public:
+ *      template <typename... Args>
+ *      Container(
+ *          type_t<in_place_t, decltype(Value(std::declval<Args>()...))>,
+ *          Args&&...);
+ *    };
+ *
+ *  void_t
+ *
+ *  A type alias for `void`. `void_t` is useful for controling class-template
+ *  and function-template partial specialization.
+ *
+ *  Example:
+ *
+ *    // has_value_type<T>::value is true if T has a nested type `value_type`
+ *    template <class T, class = void>
+ *    struct has_value_type
+ *        : std::false_type {};
+ *
+ *    template <class T>
+ *    struct has_value_type<T, folly::void_t<typename T::value_type>>
+ *        : std::true_type {};
+ */
+
+/**
+ * There is a bug in libstdc++, libc++, and MSVC's STL that causes it to
+ * ignore unused template parameter arguments in template aliases and does not
+ * cause substitution failures. This defect has been recorded here:
+ * http://open-std.org/JTC1/SC22/WG21/docs/cwg_defects.html#1558.
+ *
+ * This causes the implementation of std::void_t to be buggy, as it is likely
+ * defined as something like the following:
+ *
+ *  template <typename...>
+ *  using void_t = void;
+ *
+ * This causes the compiler to ignore all the template arguments and does not
+ * help when one wants to cause substitution failures.  Rather declarations
+ * which have void_t in orthogonal specializations are treated as the same.
+ * For example, assuming the possible `T` types are only allowed to have
+ * either the alias `one` or `two` and never both or none:
+ *
+ *  template <typename T,
+ *            typename std::void_t<std::decay_t<T>::one>* = nullptr>
+ *  void foo(T&&) {}
+ *  template <typename T,
+ *            typename std::void_t<std::decay_t<T>::two>* = nullptr>
+ *  void foo(T&&) {}
+ *
+ * The second foo() will be a redefinition because it conflicts with the first
+ * one; void_t does not cause substitution failures - the template types are
+ * just ignored.
+ */
+
+namespace traits_detail {
+template <class T, class...>
+struct type_t_ {
+  using type = T;
+};
+} // namespace traits_detail
+
+template <class T, class... Ts>
+using type_t = typename traits_detail::type_t_<T, Ts...>::type;
+template <class... Ts>
+using void_t = type_t<void, Ts...>;
+
 /**
  * IsRelocatable<T>::value describes the ability of moving around
  * memory a value of type T by using memcpy (as opposed to the
@@ -91,7 +281,7 @@ namespace folly {
 namespace traits_detail {
 
 #define FOLLY_HAS_TRUE_XXX(name)                                             \
-  BOOST_MPL_HAS_XXX_TRAIT_DEF(name)                                          \
+  FOLLY_CREATE_HAS_MEMBER_TYPE_TRAITS(has_##name, name);                     \
   template <class T>                                                         \
   struct name##_is_true : std::is_same<typename T::name, std::true_type> {}; \
   template <class T>                                                         \
@@ -118,11 +308,12 @@ struct is_trivially_copyable : std::is_trivial<T> {};
 template <class T>
 using is_trivially_copyable = std::is_trivially_copyable<T>;
 #endif
-}
+} // namespace traits_detail
 
 struct Ignore {
+  Ignore() = default;
   template <class T>
-  /* implicit */ Ignore(const T&) {}
+  constexpr /* implicit */ Ignore(const T&) {}
   template <class T>
   const Ignore& operator=(T const&) const { return *this; }
 };
@@ -139,7 +330,7 @@ struct IsEqualityComparable
           decltype(std::declval<T>() == std::declval<U>()),
           bool
       > {};
-}
+} // namespace traits_detail_IsEqualityComparable
 
 /* using override */ using traits_detail_IsEqualityComparable::
     IsEqualityComparable;
@@ -153,17 +344,24 @@ struct IsLessThanComparable
           decltype(std::declval<T>() < std::declval<U>()),
           bool
       > {};
-}
+} // namespace traits_detail_IsLessThanComparable
 
 /* using override */ using traits_detail_IsLessThanComparable::
     IsLessThanComparable;
 
 namespace traits_detail_IsNothrowSwappable {
-#if defined(_MSC_VER) || defined(__cpp_lib_is_swappable)
-// MSVC already implements the C++17 P0185R1 proposal which
-// adds std::is_nothrow_swappable, so use it instead.
+#if defined(__cpp_lib_is_swappable) || (_CPPLIB_VER && _HAS_CXX17)
+// MSVC 2015+ already implements the C++17 P0185R1 proposal which
+// adds std::is_nothrow_swappable, so use it instead if C++17 mode
+// is enabled.
 template <typename T>
 using IsNothrowSwappable = std::is_nothrow_swappable<T>;
+#elif _CPPLIB_VER
+// MSVC 2015+ defines the base even if C++17 is disabled, and
+// MSVC 2015 has issues with our fallback implementation due to
+// over-eager evaluation of noexcept.
+template <typename T>
+using IsNothrowSwappable = std::_Is_nothrow_swappable<T>;
 #else
 /* using override */ using std::swap;
 
@@ -174,7 +372,7 @@ struct IsNothrowSwappable
         noexcept(swap(std::declval<T&>(), std::declval<T&>()))
       > {};
 #endif
-}
+} // namespace traits_detail_IsNothrowSwappable
 
 /* using override */ using traits_detail_IsNothrowSwappable::IsNothrowSwappable;
 
@@ -230,8 +428,14 @@ struct Bools {
 
 // Lighter-weight than Conjunction, but evaluates all sub-conditions eagerly.
 template <class... Ts>
-using StrictConjunction =
-    std::is_same<Bools<Ts::value..., true>, Bools<true, Ts::value...>>;
+struct StrictConjunction
+    : std::is_same<Bools<Ts::value...>, Bools<(Ts::value || true)...>> {};
+
+template <class... Ts>
+struct StrictDisjunction
+  : Negation<
+      std::is_same<Bools<Ts::value...>, Bools<(Ts::value && false)...>>
+    > {};
 
 } // namespace folly
 
@@ -240,41 +444,24 @@ using StrictConjunction =
  * regular type, use it like this:
  *
  * // Make sure you're at namespace ::folly scope
- * template<> FOLLY_ASSUME_RELOCATABLE(MyType)
+ * template <> FOLLY_ASSUME_RELOCATABLE(MyType)
  *
  * When using it with a template type, use it like this:
  *
  * // Make sure you're at namespace ::folly scope
- * template<class T1, class T2>
+ * template <class T1, class T2>
  * FOLLY_ASSUME_RELOCATABLE(MyType<T1, T2>)
  */
 #define FOLLY_ASSUME_RELOCATABLE(...) \
   struct IsRelocatable<  __VA_ARGS__ > : std::true_type {};
 
 /**
- * Use this macro ONLY inside namespace boost. When using it with a
- * regular type, use it like this:
- *
- * // Make sure you're at namespace ::boost scope
- * template<> FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(MyType)
- *
- * When using it with a template type, use it like this:
- *
- * // Make sure you're at namespace ::boost scope
- * template<class T1, class T2>
- * FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(MyType<T1, T2>)
- */
-#define FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(...) \
-  struct has_nothrow_constructor<  __VA_ARGS__ > : ::boost::true_type {};
-
-/**
- * The FOLLY_ASSUME_FBVECTOR_COMPATIBLE* macros below encode two
- * assumptions: first, that the type is relocatable per IsRelocatable
- * above, and that it has a nothrow constructor. Most types can be
- * assumed to satisfy both conditions, but it is the responsibility of
- * the user to state that assumption. User-defined classes will not
- * work with fbvector (see FBVector.h) unless they state this
- * combination of properties.
+ * The FOLLY_ASSUME_FBVECTOR_COMPATIBLE* macros below encode the
+ * assumption that the type is relocatable per IsRelocatable
+ * above. Many types can be assumed to satisfy this condition, but
+ * it is the responsibility of the user to state that assumption.
+ * User-defined classes will not be optimized for use with
+ * fbvector (see FBVector.h) unless they state that assumption.
  *
  * Use FOLLY_ASSUME_FBVECTOR_COMPATIBLE with regular types like this:
  *
@@ -293,40 +480,35 @@ using StrictConjunction =
  */
 
 // Use this macro ONLY at global level (no namespace)
-#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE(...)                           \
-  namespace folly { template<> FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__) }   \
-  namespace boost { \
-  template<> FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(__VA_ARGS__) }
+#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE(...) \
+  namespace folly {                           \
+  template <>                                 \
+  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__)       \
+  }
 // Use this macro ONLY at global level (no namespace)
-#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_1(...)                         \
-  namespace folly {                                                     \
-  template <class T1> FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1>) }       \
-    namespace boost {                                                   \
-    template <class T1> FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(__VA_ARGS__<T1>) }
+#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_1(...) \
+  namespace folly {                             \
+  template <class T1>                           \
+  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1>)     \
+  }
 // Use this macro ONLY at global level (no namespace)
-#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_2(...)                 \
-  namespace folly {                                             \
-  template <class T1, class T2>                                 \
-  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1, T2>) }               \
-    namespace boost {                                           \
-    template <class T1, class T2>                               \
-    FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(__VA_ARGS__<T1, T2>) }
+#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_2(...) \
+  namespace folly {                             \
+  template <class T1, class T2>                 \
+  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1, T2>) \
+  }
 // Use this macro ONLY at global level (no namespace)
-#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_3(...)                         \
-  namespace folly {                                                     \
-  template <class T1, class T2, class T3>                               \
-  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1, T2, T3>) }                   \
-    namespace boost {                                                   \
-    template <class T1, class T2, class T3>                             \
-    FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(__VA_ARGS__<T1, T2, T3>) }
+#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_3(...)     \
+  namespace folly {                                 \
+  template <class T1, class T2, class T3>           \
+  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1, T2, T3>) \
+  }
 // Use this macro ONLY at global level (no namespace)
-#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_4(...)                         \
-  namespace folly {                                                     \
-  template <class T1, class T2, class T3, class T4>                     \
-  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1, T2, T3, T4>) }               \
-    namespace boost {                                                   \
-    template <class T1, class T2, class T3, class T4>                   \
-    FOLLY_ASSUME_HAS_NOTHROW_CONSTRUCTOR(__VA_ARGS__<T1, T2, T3, T4>) }
+#define FOLLY_ASSUME_FBVECTOR_COMPATIBLE_4(...)         \
+  namespace folly {                                     \
+  template <class T1, class T2, class T3, class T4>     \
+  FOLLY_ASSUME_RELOCATABLE(__VA_ARGS__<T1, T2, T3, T4>) \
+  }
 
 /**
  * Instantiate FOLLY_ASSUME_FBVECTOR_COMPATIBLE for a few types. It is
@@ -365,18 +547,6 @@ template <class T>
 
 FOLLY_NAMESPACE_STD_END
 
-namespace boost {
-
-template <class T> class shared_ptr;
-
-template <class T, class U>
-struct has_nothrow_constructor< std::pair<T, U> >
-    : std::integral_constant<bool,
-        has_nothrow_constructor<T>::value &&
-        has_nothrow_constructor<U>::value> {};
-
-} // namespace boost
-
 namespace folly {
 
 // STL commonly-used types
@@ -387,15 +557,8 @@ struct IsRelocatable< std::pair<T, U> >
         IsRelocatable<U>::value> {};
 
 // Is T one of T1, T2, ..., Tn?
-template <class T, class... Ts>
-struct IsOneOf {
-  enum { value = false };
-};
-
-template <class T, class T1, class... Ts>
-struct IsOneOf<T, T1, Ts...> {
-  enum { value = std::is_same<T, T1>::value || IsOneOf<T, Ts...>::value };
-};
+template <typename T, typename... Ts>
+using IsOneOf = StrictDisjunction<std::is_same<T, Ts>...>;
 
 /*
  * Complementary type traits for integral comparisons.
@@ -424,9 +587,9 @@ struct is_negative_impl<T, false> {
 // types) that violate -Wsign-compare and/or -Wbool-compare so suppress them
 // in order to not prevent all calling code from using it.
 FOLLY_PUSH_WARNING
-FOLLY_GCC_DISABLE_WARNING(sign-compare)
+FOLLY_GCC_DISABLE_WARNING("-Wsign-compare")
 #if __GNUC_PREREQ(5, 0)
-FOLLY_GCC_DISABLE_WARNING(bool-compare)
+FOLLY_GCC_DISABLE_WARNING("-Wbool-compare")
 #endif
 FOLLY_MSVC_DISABLE_WARNING(4388) // sign-compare
 FOLLY_MSVC_DISABLE_WARNING(4804) // bool-compare
@@ -449,7 +612,7 @@ bool greater_than_impl(LHS const lhs) {
 
 FOLLY_POP_WARNING
 
-} // namespace detail {
+} // namespace detail
 
 // same as `x < 0`
 template <typename T>
@@ -484,106 +647,12 @@ bool greater_than(LHS const lhs) {
     RHS, rhs, typename std::remove_reference<LHS>::type
   >(lhs);
 }
-
-namespace traits_detail {
-struct InPlaceTag {};
-template <class>
-struct InPlaceTypeTag {};
-template <std::size_t>
-struct InPlaceIndexTag {};
-}
-
-/**
- * Like std::piecewise_construct, a tag type & instance used for in-place
- * construction of non-movable contained types, e.g. by Synchronized.
- * Follows the naming and design of std::in_place suggested in
- * http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0032r2.pdf
- */
-using in_place_t = traits_detail::InPlaceTag (&)(traits_detail::InPlaceTag);
-
-template <class T>
-using in_place_type_t =
-    traits_detail::InPlaceTypeTag<T> (&)(traits_detail::InPlaceTypeTag<T>);
-
-template <std::size_t I>
-using in_place_index_t =
-    traits_detail::InPlaceIndexTag<I> (&)(traits_detail::InPlaceIndexTag<I>);
-
-inline traits_detail::InPlaceTag in_place(traits_detail::InPlaceTag = {}) {
-  return {};
-}
-
-template <class T>
-inline traits_detail::InPlaceTypeTag<T> in_place(
-    traits_detail::InPlaceTypeTag<T> = {}) {
-  return {};
-}
-
-template <std::size_t I>
-inline traits_detail::InPlaceIndexTag<I> in_place(
-    traits_detail::InPlaceIndexTag<I> = {}) {
-  return {};
-}
-
-// For backwards compatibility:
-using construct_in_place_t = in_place_t;
-
-inline traits_detail::InPlaceTag construct_in_place(
-    traits_detail::InPlaceTag = {}) {
-  return {};
-}
-
-/**
- * Initializer lists are a powerful compile time syntax introduced in C++11
- * but due to their often conflicting syntax they are not used by APIs for
- * construction.
- *
- * Further standard conforming compilers *strongly* favor an
- * std::initalizer_list overload for construction if one exists.  The
- * following is a simple tag used to disambiguate construction with
- * initializer lists and regular uniform initialization.
- *
- * For example consider the following case
- *
- *  class Something {
- *  public:
- *    explicit Something(int);
- *    Something(std::intiializer_list<int>);
- *
- *    operator int();
- *  };
- *
- *  ...
- *  Something something{1}; // SURPRISE!!
- *
- * The last call to instantiate the Something object will go to the
- * initializer_list overload.  Which may be surprising to users.
- *
- * If however this tag was used to disambiguate such construction it would be
- * easy for users to see which construction overload their code was referring
- * to.  For example
- *
- *  class Something {
- *  public:
- *    explicit Something(int);
- *    Something(folly::initlist_construct_t, std::initializer_list<int>);
- *
- *    operator int();
- *  };
- *
- *  ...
- *  Something something_one{1}; // not the initializer_list overload
- *  Something something_two{folly::initlist_construct, {1}}; // correct
- */
-struct initlist_construct_t {};
-constexpr initlist_construct_t initlist_construct{};
-
 } // namespace folly
 
 // Assume nothing when compiling with MSVC.
 #ifndef _MSC_VER
-// gcc-5.0 changed string's implementation in libgcc to be non-relocatable
-#if __GNUC__ < 5
+// gcc-5.0 changed string's implementation in libstdc++ to be non-relocatable
+#if !_GLIBCXX_USE_CXX11_ABI
 FOLLY_ASSUME_FBVECTOR_COMPATIBLE_3(std::basic_string)
 #endif
 FOLLY_ASSUME_FBVECTOR_COMPATIBLE_2(std::vector)
@@ -592,93 +661,8 @@ FOLLY_ASSUME_FBVECTOR_COMPATIBLE_2(std::deque)
 FOLLY_ASSUME_FBVECTOR_COMPATIBLE_2(std::unique_ptr)
 FOLLY_ASSUME_FBVECTOR_COMPATIBLE_1(std::shared_ptr)
 FOLLY_ASSUME_FBVECTOR_COMPATIBLE_1(std::function)
-
-// Boost
-FOLLY_ASSUME_FBVECTOR_COMPATIBLE_1(boost::shared_ptr)
 #endif
 
-#define FOLLY_CREATE_HAS_MEMBER_TYPE_TRAITS(classname, type_name) \
-  template <typename T> \
-  struct classname { \
-    template <typename C> \
-    constexpr static bool test(typename C::type_name*) { return true; } \
-    template <typename> \
-    constexpr static bool test(...) { return false; } \
-    constexpr static bool value = test<T>(nullptr); \
-  }
-
-#define FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(classname, func_name, cv_qual) \
-  template <typename TTheClass_, typename RTheReturn_, typename... TTheArgs_> \
-  class classname<TTheClass_, RTheReturn_(TTheArgs_...) cv_qual> { \
-    template < \
-      typename UTheClass_, RTheReturn_ (UTheClass_::*)(TTheArgs_...) cv_qual \
-    > struct sfinae {}; \
-    template <typename UTheClass_> \
-    constexpr static bool test(sfinae<UTheClass_, &UTheClass_::func_name>*) \
-    { return true; } \
-    template <typename> \
-    constexpr static bool test(...) { return false; } \
-  public: \
-    constexpr static bool value = test<TTheClass_>(nullptr); \
-  }
-
-/*
- * The FOLLY_CREATE_HAS_MEMBER_FN_TRAITS is used to create traits
- * classes that check for the existence of a member function with
- * a given name and signature. It currently does not support
- * checking for inherited members.
- *
- * Such classes receive two template parameters: the class to be checked
- * and the signature of the member function. A static boolean field
- * named `value` (which is also constexpr) tells whether such member
- * function exists.
- *
- * Each traits class created is bound only to the member name, not to
- * its signature nor to the type of the class containing it.
- *
- * Say you need to know if a given class has a member function named
- * `test` with the following signature:
- *
- *    int test() const;
- *
- * You'd need this macro to create a traits class to check for a member
- * named `test`, and then use this traits class to check for the signature:
- *
- * namespace {
- *
- * FOLLY_CREATE_HAS_MEMBER_FN_TRAITS(has_test_traits, test);
- *
- * } // unnamed-namespace
- *
- * void some_func() {
- *   cout << "Does class Foo have a member int test() const? "
- *     << boolalpha << has_test_traits<Foo, int() const>::value;
- * }
- *
- * You can use the same traits class to test for a completely different
- * signature, on a completely different class, as long as the member name
- * is the same:
- *
- * void some_func() {
- *   cout << "Does class Foo have a member int test()? "
- *     << boolalpha << has_test_traits<Foo, int()>::value;
- *   cout << "Does class Foo have a member int test() const? "
- *     << boolalpha << has_test_traits<Foo, int() const>::value;
- *   cout << "Does class Bar have a member double test(const string&, long)? "
- *     << boolalpha << has_test_traits<Bar, double(const string&, long)>::value;
- * }
- *
- * @author: Marcelo Juchem <marcelo@fb.com>
- */
-#define FOLLY_CREATE_HAS_MEMBER_FN_TRAITS(classname, func_name) \
-  template <typename, typename> class classname; \
-  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(classname, func_name, ); \
-  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL(classname, func_name, const); \
-  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL( \
-      classname, func_name, /* nolint */ volatile); \
-  FOLLY_CREATE_HAS_MEMBER_FN_TRAITS_IMPL( \
-      classname, func_name, /* nolint */ volatile const)
-
 /* Some combinations of compilers and C++ libraries make __int128 and
  * unsigned __int128 available but do not correctly define their standard type
  * traits.